It’s been said that there’s no replacement for displacement
and that’s certainly true when it comes to the windowrattling
power of the ZZ502/502. This big Rat engine
makes one horsepower for each of its 502 cubic inches
and also churns out 567 tugboat-like pound-feet of
torque—enough to pull the chrome off a Dearborn
bumper!
The ZZ502/502 uses aluminum big-valve, oval-port heads
which flow tremendous air to satisfy the demands of the
4.47-inch bores and 4.00-inch-stroke crankshaft. Forged
reciprocating components ensure high-performance
durability and longevity.

• TECH SPECS: ZZ502/502
• Part Number: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12496962
• Engine type: . . . . . . . . . . . . . . . . . . . . . . . . . Chevy big-block V-8
• Displacement (cu in): . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
• Bore x stroke (in): . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.47 x 4.00
• Block: . . . . . . . . . . . . . . . . . . . . cast iron with 4-bolt main caps
• Crankshaft: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . forged steel
• Connecting rods: . . . . . . . . . . . . . . . . forged steel, shot peened
• Pistons: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . forged aluminum
• Camshaft type: . . . . . . . . . . . . . . . . . . . . . . . . . . hydraulic roller
• Camshaft lift (in): . . . . . . . . . . . . . . . . .527 intake / .544 exhaust
• Camshaft duration (@.050 in): . . . . . 224° intake / 234° exhaust
• Cylinder heads: . . . . . . . aluminum oval port; 110cc chambers
• Valve size (in): . . . . . 2.25 intake / 1.88 exhaust; stainless steel
• Compression ratio: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.6:1
• Rocker arms: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . stamped steel
• Rocker arm ratio: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7:1
• Flexplate: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-inch
• Recommended fuel: . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 octane
• Ignition timing: . . . . . 8° BTDC @ 800 rpm; 36° total @ 5000 rpm
• Maximum rpm: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5800

INSTALLATION NOTES
• Carburetor and starter not installed because
of crate fitment.
• Clutch linkage boss is cast into block, but must be drilled and
tapped. When using cast iron exhaust manifolds, lower head
bolts may need to be replaced with bolts with shorter heads,
for clearance.
• Requires electric fuel pump because Gen VI block
has no mechanical pump boss
• Comes with a 14-inch automatic transmission flexplate.
• Not intended for marine applications.